This is a somewhat common Mac crash that has occurred since at least 4.14 and into 4.17. Users have not provided any descriptions of their actions when the crash occurred.
The callstack contains little information, and is most similar to [Link Removed]
Callstack from Log
[2017.09.11-18.29.14:159][709]LogStaticLightingSystem: Warning: Failed to build lighting!!! Lighting build failed. [2017.09.11-18.29.14:160][709]DumpUnbuiltLightIteractions [2017.09.11-18.29.14:160][709]Lights with unbuilt interactions: 1 [2017.09.11-18.29.14:160][709] Light LightSource [2017.09.11-18.29.14:160][709] [2017.09.11-18.29.14:160][709]Primitives with unbuilt interactions: 1 [2017.09.11-18.29.14:160][709] Primitive StaticMeshComponent /Game/NewMap.NewMap:PersistentLevel.SM_Chair_2.StaticMeshComponent0 [2017.09.11-18.29.14:226][710]Cmd: MAP CHECK NOTIFYRESULTS [2017.09.11-18.29.14:226][710]MapCheck: New page: NewMap - Sep 12, 2017, 12:29:14 AM [2017.09.11-18.29.14:227][710]MapCheck: Error: WorldSettings_1 Maps need lighting rebuilt [2017.09.11-18.29.14:257][710]MapCheck: Map check complete: 1 Error(s), 0 Warning(s), took 31.024ms to complete. [2017.09.11-18.29.31:841][900]LogMac: === Critical error: === SIGSEGV: invalid attempt to access memory at address 0x18 [2017.09.11-18.29.31:841][900]LogMac: objc_msgSend() Address = 0xbd21b05d (filename not found) [in libobjc.A.dylib] invocation function for block in FMacWindow::Show() Address = 0x53b366e (filename not found) [in UE4Editor-Core.dylib] FCocoaRunLoopSource::Process(__CFString const*) Address = 0x535ca44 (filename not found) [in UE4Editor-Core.dylib] -[FCocoaRunLoopSourceInfo perform] Address = 0x535c496 (filename not found) [in UE4Editor-Core.dylib] __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__() Address = 0xa83af321 (filename not found) [in CoreFoundation] __CFRunLoopDoSources0() Address = 0xa839021d (filename not found) [in CoreFoundation] __CFRunLoopRun() Address = 0xa838f716 (filename not found) [in CoreFoundation] CFRunLoopRunSpecific() Address = 0xa838f114 (filename not found) [in CoreFoundation] RunCurrentEventLoopInMode() Address = 0xa78efebc (filename not found) [in HIToolbox] ReceiveNextEventCommon() Address = 0xa78efcf1 (filename not found) [in HIToolbox] _BlockUntilNextEventMatchingListInModeWithFilter() Address = 0xa78efb26 (filename not found) [in HIToolbox] _DPSNextEvent() Address = 0xa5e88a54 (filename not found) [in AppKit] -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] Address = 0xa66047ee (filename not found) [in AppKit] -[NSApplication run] Address = 0xa5e7d3db (filename not found) [in AppKit] tchar_main(int, wchar_t**) Address = 0x50960f3 (filename not found) [in UE4Editor] main() Address = 0x5095979 (filename not found) [in UE4Editor] start() Address = 0xbdb0f235 (filename not found) [in libdyld.dylib]
repro steps currently unknown
SEGV_MAPERR at 0x18 libobjc.A.dylib!Unknown() UE4Editor-Core.dylib!<Unknown> UE4Editor-Core.dylib!FCocoaRunLoopSource::Process() UE4Editor-Core.dylib!<Unknown> CoreFoundation!Unknown() CoreFoundation!Unknown() CoreFoundation!Unknown() CoreFoundation!Unknown() HIToolbox!<Unknown> HIToolbox!<Unknown> HIToolbox!<Unknown> AppKit!<Unknown> AppKit!-[NSApplication() AppKit!<Unknown> UE4Editor!tchar_main() UE4Editor!<Unknown> libdyld.dylib!<Unknown>
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